Safety spring-barrel.



R. L. MARSHALL. SAFETY SPRING BARREL.

.APPLIOATION I'ILED NOV. 25, 1910.

- Patented June 27, 1911.

WITNESSES:

H 5 M M F i m ATTORNEYS THE NORRIS PETERF co., wnsummcu, u. c

UNITED STATES ATENT GFFICE.

ROBERT L, MARSHALL, OF ELIZABETHTOWN, KENTUCKY.

SAFETY SPRING-BARREL.

Application filed November 25, 1910.

To all whom it may concern:

Be it known that I, ROBERT L. MARsHALL, a citizen of the United States, and a resident of Elizabethtown, in the county of Hardin and State of Kentucky, have made certain new and useful Improvements in Safety Spring-Barrels, of which the following is a specification.

My invention relates to spring barrels for watch movements, and it consists in the combinations, constructions and arrangements herein described and claimed.

an object of my invention to provide a spring barrel for a watch, disposed upon a solid arbor which extends through the entire length of the barrel, thereby insuring stability.

A further object of my invention is to provide a device in which the size of the jewel holes are reduced. thereby lessening friction, without sacrificing stability.

A further object of my invention is to provide a spring barrel and an arbor therefor, having very few parts but with every advantage that is possessed by devices of similar nature of far more complex struc ture.

Other objects and advantages will appear in the following specification and the novel features of the device will be particularly pointed out in the appended claims.

My invention is illustrated in the accom panying drawing forming part of this application in which similar reference characters indicate like parts in the several views and in which Figure l is a central section through the spring barrel in a plane through its axis, Fig. 2 is a section at right angles to Fig. 1 along the line 22, and Fig. 3 shows perspective views of the barrel and its arbor.

In carrying out my invention I provide an arbor such as that shown in Fig. 3. This arbor consists of a main cylindrical portion 1 having an integral beveled shoulder 2 and a reduced portion 3 outside of the shoulder arranged to enter and be supported by the movement plate A. The opposite end of the arbor has a cylindrical reduced portion 4-.

The spring barrel proper consists of a cylinder 5 having a closed end 5 to which is secured an extension 6. This extension really consists of three integral portions; a beveled shoulder 6 which. as stated, is secured to the end 5", a central hollow cylin- Specification of Letters Patent.

Patented June 2'7, 1911. Serial No. 594,058.

drical portion 6 and an end portion 6 having a squared exterior surface. The cylindrical portion 6 is bored out to receive the main cylindrical member 1 of the arbor and. the squared portion 6 is bored out to re ceive the reduced end 4 of the arbor as clearly shown in Fig. 1.

Arranged to cooperate with the barrel 5 is a wheel 7 of the shape shown in Fig. 1. This wheel consists of a cylinder closed at one end provided with a series of integral teeth 7 extending around the wheel near the open end. The wheel 7 is provided with an integral hub 8, which is bored out to receive the arbor 1 and is provided with recesses in its ends to receive the jeweled bearings 9 and 10. On the outside of the hub is a hook 11 to which one end of the main spring 12 is attached, the other end being attached to a hook 5 on the inner side of the barrel 5. The cylindrical portion 6 of the extension 6 passes through the movement plate B. On the squared portion 6 is a winding wheel 13.

From the foregoing description of the various parts of the device the operation thereof may be readily understood. Power is applied to the winding wheel 13 and this in turn causes the revolution of the spring barrel 5 upon the arbor 1. The friction is borne by the jeweled bearings 10 and 11. The rotation of the spring barrel tightens the spring 12. The gear 13 is held, of course, by a pawl (not shown) and the driving wheel 7 which is slipped over the spring barrel, is caused to revolve and hence to drive the watch train.

In Fig. 1, it will be observed that the shoulder 2 bears against the outside of the jewel 10 of the wheel 7 to keep it in place. In order to get at the main spring it is only necessary to remove one of the movement plates, as for instance the plate A. The arbor 1 may then be pulled outwardly and the barrel and wheel separated. Since the barrel and the extension 6 are integral, and since the wheel 7 and its hub are integral, and the arbor 1 and its shoulder 2 and extension t are integral, there are only three parts comprising the complete spring barrel. This I regard as one of the main features of my invention, since it simplifies the construction to a great extent. It will be noted that the jeweled bearings 9 and 10 are at the ends of the hub. In other words, the spring barrel has its bearings at a maximum distance apart. The stability of the device is thereby increased. The size of the arbor 1 may be greatly reduced since the bearings are located close to the point of support of the arbor. There is therefore no liability of the arbor being bent. This feature I also regard as very important, since in many watch movements the arbors must necessarily be large in order to stand the strain to which they are subjected.

In Fig. 1, I have illustrated the jeweled bearings 9 and 10, but it is not to be under stood that. these bearings must necessarily be as large in proportion to the other parts as they are shown in the drawings. In fact, it is possible to make them much smaller than those in ordinary use, because, as stated, the arbor about which these hearings rotate may be made small without sacrificing the strength of the device.

I claim 1. In a ateh mechanism, a pair of movement plates, a cylindrical arbor having a reduced end portion secured in one movement plate and being provided with a shoulder adjacent said reduced end portion, the opposite end of the arbor being); also reduced, a barrel comprising a cylinder having a closed end, an extension of said cylinder secured to said closed end, said extension being bored out to receive the main arbor and havinn' :1 smaller bore to receive the reduced end of said arbor, the external surface of the extension to ard said small bore being squared, a driving wheel comprising a hub arranged to tit over said arbor, said. hub being recessed at its ends, jeweled bearings carried by said hub .in said recesses and be ing; provided with openings to receive said arbor, said hub having a hook on its periphery for securing one end of the main spring,

and said barrel having a hook on its inner side for securing the other end of the main sprinp.

2. In a watch mechanism, a pair of movement plates, a cylindrical arbor having a reduced end portion secured in one movement plate and being provided with a shoulder adjacent said reduced end portion, the opposite end of the arbor being also reduced, a barrel comprising a cylinder having a closed end, an extension of said cylinder secured to said closed end, said extension being bored to receive the arbor and its reduced end, a driving wheel comprising a hub ar "anged to lit over said arbor, said hub being recessed at its ends, jeweled bearings carried by said hub in said recesses and being provided with openings to receive said arbor, the integral shoulder on said arbor abutting the side of the driving wheel and forming a guide for the latter.

3. In a watch mechanism, a pair of movement plates, an arbor provided with a shoulder secured atone end in one of said movement plates, a spring: barrel comprising a cylinder having a closed end and provided with a central bored extension, said extension being secured in the other movement plate, and a driving: wheel comprising a cylinder having one end closed and having a central hub arranged to enter within said barrel and being; provided at its ends with recesses, jeweled bearings carried in said recesses tlior supporting the driving: wheel upon the arbor, and means carried by said hub and said barrel for the attachment of the main spring.

ROBERT L. hiirrRSl'lrUiL. lVitnesses:

Nonrn C. rtMnN'r, S'raxnnr P. l-losnrxsox.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. C. 

